Functional Genomics of Transfer Cells

PI: Christopher G. Taylor（俄亥俄州立大学和Donald Danforth植物科学中心）CoPIs: Lauren McIntyre和Karen E. Koch（佛罗里达大学- Gainsville）该项目的目的是定义和表征在转移细胞发育和功能中重要的基因。转移细胞促进糖和氨基酸从细胞外空间向植物细胞内部的大量运动。例如，在胚乳组织中形成转移细胞，其中同化物从母体组织转移到发育中的种子。已知某些生物营养相互作用也可诱导具有类似功能的细胞的形成。根结线虫诱导形成多核细胞，称为巨细胞，这是线虫营养的唯一来源。由于它们的功能相似性，来自种子的转移细胞和线虫诱导的巨细胞具有许多相同的形态学特征，包括细胞壁增厚和高度内陷、细胞质致密、内质网丰富、小液泡和线粒体众多。具有转移细胞样功能的细胞是科学研究的重要对象，因为它们的活动涉及许多鲜为人知的分子和细胞学运输过程，它们对植物和特定生物营养植物病原体的生存至关重要。利用激光捕获显微解剖技术，研究拟南芥和玉米种子和线虫诱导的巨细胞中与转移细胞发育和功能相关的基因。基因独特和共同的胚乳转移细胞和巨细胞将检查其表达模式在植物发育和线虫侵染。蛋白质的亚细胞定位将有助于分配蛋白质的角色来转移细胞功能。T-DNA插入系（拟南芥）和转座子标记系（玉米）将用于检查种子发育或线虫寄生期间基因（及其编码的蛋白质）的功能。拟南芥和玉米突变体的分子和生化分析将为传递细胞在同化物运动中的作用提供更多的信息。所有研究材料将在项目网站（http://www.danforthcenter.org/taylor/）上进行编目和描述，并提供给研究社区。这些实验将为巨细胞和转移细胞功能的分子基础提供有价值的见解，并且鉴于根结线虫作为植物病原体的重要性以及转移细胞在种子、果实和/或生物量形成中的重要性，这些实验将具有高度的实际相关性。更广泛的影响：本项目将提供三种方法来扩大科学的影响。首先，暑期本科生实习生将通过丹佛斯中心的暑期REU实习计划参与该项目。该项目致力于培养学生对基础科学的兴趣和理解，重点是招募代表性不足的少数民族。第二，我们将通过教师研究教育（RET）项目提供暑期教师奖学金。参与其中的科学教师受益于在活跃的实验室工作所提供的知识和经验。第三，这个项目将开发几个DNA微阵列旅行箱，教高中生微阵列及其用途。高中科学教师将接受培训，学会使用主干，并根据微阵列技术制定和管理课程计划。Trunk项目将包括课程计划、设备、材料、在线资源和学生实践活动，以展示微阵列的原理。这些短裤将在各个学区共享，惠及圣路易斯及周边地区的各种学生。

PI: Christopher G. Taylor (Ohio State University and the Donald Danforth Plant Science Center)CoPIs: Lauren McIntyre and Karen E. Koch (University of Florida - Gainsville)The aim of this project is to define and characterize genes important in the development and function of transfer cells. Transfer cells facilitate the mass movement of sugars and amino acids from extracellular spaces to the inside of plant cells. For example, transfer cells are formed in endosperm tissues where assimilates are transferred from maternal tissues to the developing seed. Certain biotrophic interactions are also known to induce the formation of cells with similar function. Root-knot nematodes induce the formation of multinucleated cells, called giant cells, which serve as the exclusive source of nematode nutrition. Due to their functional similarities, transfer cells from seeds and nematode-induced giant cells share many of the same morphological characteristics including thickened and highly invaginated cell walls, dense cytoplasm, abundant ER, and numerous small vacuoles and mitochondria. Cells with transfer cell-like function are eminent objects of scientific interest since their activity involves a number of poorly understood molecular and cytological transport processes and they are crucial for the survival of both plants and specific biotrophic plant pathogens. Using laser capture microdissection, the transcriptome of transfer cells from developing seeds and from nematode-induced giant cells of Arabidopsis and maize will be examined for genes involved in transfer cell development and function. Genes unique and common to endosperm transfer cells and giant cells will be examined for their patterns of expression during plant development and nematode infestation. Sub-cellular localization of proteins will aid in assigning the role of proteins to transfer cell functions. T-DNA insertion lines (Arabidopsis) and transposon tagged lines (maize) will be used to examine the function of genes (and the proteins they encode) during seed development or nematode parasitism. Molecular and biochemical analysis of Arabidopsis and maize mutants will provide additional information on the role of transfer cells in assimilate movement. All research materials will be cataloged and described on a project website (http://www.danforthcenter.org/taylor/) and made available to the research community. These experiments will provide valuable insight into the molecular basis of giant and transfer cell function and will be of high practical relevance given the importance of root-knot nematodes as plant pathogens and the importance of transfer cells in the formation of seed, fruit and/or biomass. Broader Impacts: Three approaches to broadening the impact of science will be provided in this project. First, summer undergraduate interns will get involved in the project through the summer REU internship program at the Danforth Center. This program is dedicated to fostering an interest and understanding in basic science among students with an emphasis on the recruitment of underrepresented minorities. Secondly, we will provide summer teacher fellowships through a Research Education for Teachers (RET) program. The participating science teacher benefits from the knowledge and experience provided by working in an active laboratory. Thirdly, this project will develop several DNA Microarray Traveling Trunks that teach high school students about microarrays and their uses. High school science teachers will be trained to use the trunk and develop and administer lesson plans based on microarray technology. The Trunk program will incorporate lesson plans, equipment, materials, online resources and hands-on student activities to demonstrate the principals of microarrays. The Trunks will be shared among the school districts, reaching a diverse array of students across the St. Louis and surrounding areas.